Adjustable seat



Aug. 31, 937- LE GRAND s. WHEDON ET AL' 2,091,899

1DJUSTABLE SEAT Filed Nov. 20, 1934 4 Sheets-Sheet 1 INVENTORS Lefimndswhedon, Amer; Afirmnefl .s.

uymonhkousseau, a ATTORNEYS Aug. 3i; 1937.

ADJUSTABLE SEAT Filed NOV. 20, 1954. 4'Sh9ets-Shest 5 Fig.1.

163 lNv'ENTos LefirandS.Whadon,

. AlbcflAflrmmna Raymonmlousseau,

ATTORNEYS Patented Aug. 31, 1937 UNITED STATES.

2,091,899 ADJUSTABLE SEAT Le Grand S. Whedon Medina, N Y.

and Albert A. Grinnell,

and Raymon E. Rousseau, Buffalo,

Application November 20, 1934, Serial No. 753,968

20 Claims.

' This invention relates to adjustable seat structure for installationin vehicles or in other structures, and it has particular relation to animproved controlling and operating mechanism for Ya .seat structurewherein seat supporting members, seat back and seat bottom can berelatively moved to conform readily to the position desired of personshaving various heights, weights, or other characteristics that mightrequi e either average or special seating arrangements.

The invention is concerned with improved controlling devices adapted tobe incorporated in. an

adjustable seat structure and involves an improvement over the type ofseat structure described generally in the application of Albert A.Grinnell, Serial No. 694,815, filed October 23, 1933, for Seatconstruction, wherein an occu-' pant while seated may adjust theelements of theseating structure to provide comfortable upright Mseating posture for the back, or the seat may be so adjusted as to movethe seat bottom with respect to its angular relation to the horizontal,in order to raise and lower portions thereof in conformity with thedesired positions or physical characteristics of various types ofpersons, or

the seat bottom may be moved bodily to various horizontal positionsforwardly and rearwardly, while portions of the seat back can beadjusted forwardly and rearwardly at will, in addition to 80 followingin part the movement of the seat bottom.

One of the principal features of the invention is exemplified in thestructure of a controlling mechanism that is incorporated in a seatraising or lifting device that includes mechanism for locking orunlocking the seat structure in any of a series of positions while thelocking mechanism is substantially free from binding influences thatmight tend to interfere with uniform action of the mechanical parts ofthe structure.

In angular movements of the seat parts about supporting pivots and uponpredetermined radii,

the force eifect of a given weight carried upon the seat varies; thatis, when the radius of support is substantially vertical the leverage isvery slight but as the radius approaches the horizontal the leverageincreases. The lifting mech-, anism operates about predetermined axesand through predetermined angles and an improved arrangement ofresilient means is provided to compensate forthe different eifects ofweights at the different angular positions of s pporting rocker arms.

Another important feature of the invention is exemplified in an improvedtype of locking mechanism for maintaining the seat structure in variouspositions of adjustment, and which cooperates with rocker arm supportsof portions of the seat structure.

In the drawings:

Fig. 1 is a perspective of a seat structure in which the invention isincorporated;

Fig. 2 is a plan of the lower seat supporting structure and operatingmechanism for adjusting the seat structure; 4 v 10 Fig. 3 is a verticalsection taken substantially along the line III-III of Fig. 2;

Fig. 4 is a fragmentary ctoss section oi a looking mechanism and takensubstantially along the line IV-IV of Fig. 3;

Fig. 5 is a fragmentary cross section taken substantially along the lineV'V of Fig. 3;

Fig. 6 is a fragmentary cross section taken substantially along the lineVI--VI of Fig. 3;

Fig. '7 is a side elevation of another form of M lifting and lockingmechanism for the seat structure;

Fig. 8 is a fragmentary elevation, partially in section and on a largerscale, of lever and locking elements of the seat adjusting mechanism;

Fig. 9 is a substantially vertical section taken along the line IX-IX ofFig. 8;

Fig. 10 is a fragmentary elevation showing in detail portions of alocking dog for the seat locking mechanism.

Fig. 11 is a fragmentary plan illustrating another form of arrangementof lifting springs and adjusting mechanism for the seat structure and'with certain elements omitted for the sake of clearness; and

Fig. 12 is a fragmentary side elevation of the structure shown in Fig.11 and with, certain elements added.

In practicing the invention, a seat structure I0 is installed upon asuitable support H which 40 can be in the form of a vehicle floor, orthe like, and includes supporting bars l5 that have pivotalconnectionsl6 securing them to the supporting floor.

A lifting and adjusting unit 20 which is frame- 45 like in constructionincludes a. front rocker arm 22 and a rear rocker a v 23 on each side bfthe seat structure. v

Transverse rods 25 and 26, extending from one sldepf the unit to theother are integrally connected to the front and rear rocker arms 22 and'23, respectively, and are rotatablymounted in bearing brackets 21carried rigidly upon the supporting bars IS. 'I'he rocker arms 22 and 23extend rigidly and substantially at right angles to the transverse rods25 and 26 and are pivotally movable in parallel relation fromsubstantially horizontal to substantially vertical positions.

The lifting unit 20 further includes a substantially horizontal frame 29having bearing brackets 38 in which oif-set front and rear bearingportions 32 and 33 of the rocker arms are journalled. In their parallelmovement the rocker arms 22 and 23 carry the frame 29 substantiallyhorizontally in all of their positions. Additional upholstery supportingframework 35 extending upwardly and rearwardly from the horizontal frameis rigidly secured to the latter and constitutes a part of the rear ofthe seat structure [0, as well as providing frame portions 36 extendingto the front portion of the frame 29. A plurality of arms 31 and 38 arerigidly secured upon, or formed integrally with, the intermediateportion of the transverse bearing rod 26 and these arms extend at anglesto each other and at angles to the rocker arms 23, with reference to theaxis of the bearing rod 26, although they are spaced in differentplanes. Coil springs 40 and 4|, normally under tension, and having endpor- 25 tions connected, as indicated at 42 and 43, to the outer endportions of the arms 31 and 38, respectively, also have their oppositeends connected, as indicated at 48 and 49, respectively, to intermediateportions of the transverse rod 25. It will be observed that, when therocker arms 22 and 23 are in a lowered or substantially horizontalposition, the arm 31 is in a substantially vertical position and the arm38 is disposed subr stantially 45 degrees to the vertical. In thisposition both springs 48 and 4| have a favorable leverage relation tothe arms and both springs exert substantially their maximum liftingforce with respect to the frame 29.- As the rocker arms 22 and 23approach upright positions the force required to lift the frame 29 andloads carried thereon decreases and at the same time the relative forceexerted by the springs decreases because, in the upright position of therocker arms 22 and 23, the tension in the springs has been 45considerably spent and the arm 31 is disposed at only a slight angle tothe horizontal. Therefore, there is only slight lever action exertedupon the rod 26 through the arm 31. Under these conditions, the otherarm 38 is disposed at an angle of 50 approximately 60 degrees to thehorizontal and is tilted toward-the spring anchoring connection 49. Thislatter spring is still exerting considerable force and has much morefavorable leverage advantage with respect to the arm 38 than the otherspring and exertssuflicient force to maintain the frame 29 in its liftedposition and can resist considerable weight upon the frame 29.

The bearing portions 32 and 33 of the rocker arms at one side of theunit 28 are provided with upwardly projecting integral angularextensions 58 and 52, respectively, which are parallel to each other andare connected at points spaced from the axes of the bearing portions 32and 33 by means of a locking device 53 having' piv'otal con- 05 nections55 and 56 thereon. The extension 68 serves as a portion of an operatinglever or handle. The locking device includes a bar portion 51 whichserves as a brace to cooperate with the frame 29 in maintaining properparallel rela- 7 tion of the rocker arms and compensating for whateverlooseness that may occur in the bearing brackets 21 and 38 supportingthese rocker arms.

' A line joining the axes of the connections 55 and 56 is parallel to aline joining the axes of the bear- 75 ing portions 32 and 33 whichlatter line is, in turn,

parallel to a line joining the axes of the transverse bearing rods 25and 26. These imaginary lines of course are assumed to be in parallelvertical planes, or in the same vertical plane, depending upon theposition of the parts with reference to the structure shown in Fig. 3.

The forward end of the locking device 53 is formed with a rigid sector60 that has an arcuate rack portion '62, the line of curvature of whichis drawn about the axis of the pivotal connection 55 as a center. Thearcuate rack portion 62 faces downwardly and in the rocking motion ofthe rocker arms the edge of this rack portion passes transversely acrossthe upper extension 58 of the front rocker arm at a predetermined pointadjacent the side thereof. A locking member 63 having rollers 65 (Fig.6) mounted thereon is movable into and out of engagement with the rackportion 62 of the locking device, and is carried upon the lower endportion of a handle 66 mounted in telescoping'relation upon the upperprojecting end extension 58 of the rocker arm 22.

A socket 61 formed in the slidable handle supports one end of a coilspring 68 and the other end of this spring engages the outer end of therocker arm extension 56. Normally the spring 68 urges the locking memberinto engagement with the arcuate rack portion 62 and thus locks therocker arms against pivotal movement. However, by telescoping the handledownwardly upon the extension 50 the locking member 63 carried therebycan be released from the rack portion to permit rocking motion of thearms 22 and 23. The bar portion 51 of the locking device remains insubstantially the same parallel relation to the seat bottom 29 in all ofits movements. A second adjusting-bar 10 having an intermediate slot 12is slidably supported by the pivotal connection 55 engaging in the slotand is provided at its lower portion with that straddle the offsetbearing portion 32 of the .rocker arm 22 to insure proper guiding of thelowerportion of the bar longitudinally of the rocker arm extension. Theupper portion of the bar 18 is formed with a laterally projecting handle15 to facilitate its operation. An arcuate actuating finger 18 is bar10-and the line of curvature of this finger in its normal position isdrawn substantially about the axis of the bearing portion 32 of thefront rocker arm. One end of a latch 11 is disposed I adjacent the uppersurface of the finger and upward sliding motion of the bar 16 causes thelatch to be pivoted about its pivotal connection 18 on the frame 29 andagainst the action of a coil spring 19 that has one end engaging in asocket 88 in the frame and its other end engaging the end portion of thelatch opposite that adjacent the finger 16. The latch 11 is thusreleasably engaged with a rack 82 rigidly secured upon' the lowersurface of a seat bottom 83. K

v A pair of straps 86, bowed upwardly to provide rounded bearingsurfaces, support the front por-' tion of the seat bottom, and suitablefastening devices 86 secure the straps to the upper surface of the frame29.

The rear portion of the seat bottom 83 is provided with upright stirrups81 rigidly secured thereto and the upper ends of the stirrups are-.pivotally conniactedfas indicated at 88, to the upper ends of uprightrocker arms 88. A hearin rod 92 integrally connecting the rocker arms toform an equalizer is disposed transversely of the.

upper rear portion of the frame and is provided parallel legs 13' withbearing brackets secured to the frame 29. The rear of the seat bottom 83is thus suspended from the upper ends of the rocker arms I 90 and byreleasing the latch 'I'I from the rack 02 the seat bottom can beadjusted forwardly and rearwardly to any position commensurate with thelength of the rack and distance of the lower rear portion of the seatbottom from the upper surface of the frame 29. In the forward adjustmentof the seat bottom 83 its rear portion is 10 slightly lowered as theupper ends of the rocker arms 90 tilt forward and follow a downwardarcuate path. Thus it will be apparent that the seat bottom 83 can beadjusted with respect to the frame 29 and that the seat bottom and the15 frame can be adjusted concurrently as a unit upon the rocker arms 22and 23 and by the ad-. justing device 53.

The stirrups 81 secured to the rear portion of the seat bottom 83 areprovided with rearward- 20 ly extending angular portions 95. Inwardlydirected guiding projections or lugs 96 formed upon the rear ends ofeach angular portion 95 slidably receive between them the lower cut awayside edges 91 of a seat back I00, and thus the lower 25 portion of thelatter is maintained in proper relation to the adjacent portion of theseat bottom 83 with which it moves regardless of whether the movement isforward or rearward, but the seat bottom is movable upwardly withrespect to the seat back.

Torsion springs I02 having fastening devices I03 connecting end portionsthereof to rear vertical frame members I05 of the seat back have I theiropposite end portions connected by means of fastening devices I06 to theframework 35 of the seat structure I0. It will be observed that thelower extremities of the torsion springs are located adjacent theintermediate portion of the seat back with reference to the upper andlower 40 portions thereof and that these extremities are formed intotorsion coils I01. These torsion springs are normally undertension, and,in ad dition to supporting the seat back upon the framework 35,, theyconstantly urge the seat back 45 in a forward direction. The coils I01also pro-' vide a hinge-like connection between the seat back I00 andthe framework 35, and hence, the seat back can be moved in tiltingmotions either backwardly or forwardly about these coils in ad- 50dition to the bodily movement forwardly and rearwardly. An individualseated upon the seat structure can overcome the forward urge of thetorsion springs against the seat back by exerting backward pressureagainst the latter, and hence, 55 the proper position for maximumcomfort, as to the seat back, can be assumed conveniently and with ease.I

In controlling the movement of the seat back I00 with respect to thesupporting framework 35,

60 an arcuate rack arm IIO, that has a pivotal connection Il2 securingit at one end to the frame support, is so mounted that its other endextends through a slot II 3 formed in a plate II5 that is secured to therear portion of the seat back. The

65 rear of the seat back is recessed, as indicated at 6, in order toprovide for extension of the arm IIO through the slot into'the seat backduring movements of the latter incidental to adjustments. The lowersurface or the rack arm H0 70 rests slidably upon the lower wall of theslot 3.

Back teeth III are formed. upon the upper side of the rack arm and. oneend of a latch Ill, that has an intermediate pivot connection "0securing it to the plate 5 at the rear of the seat 5 back, en8a8esbetween two adjacent teeth II! of' .movement of the seat bottom alongwith the the rack to lock the seat back in various positions ofadjustment. The end portion of the latch opposite the rack has aflexible actuator I20 connected thereto that is incased in a flexibletube I22 and is also connected to an intermediate portion of a.lever I23that is pivoted, as indicated at I 25,'to the side portion of the seatback I00. The lever projects forwardly and presents a knob or handle I20at the side of the seat at a location convenient for actuation by aperson seated upon the seat structure. The tube I22 is secured to theseat back frame by means of .a bracket I21. mounted upon the rearportion of'the latter.

By manipulating the lever I23 the latch I I8 is released from theteethof the rack H0 and the springs I02 urge the'seat back forwardly to thedesired position of adjustment while the lower portion of the seat backcan pivot or slide between the lugs 96. Then the lever is released topermit the latch to resume its engagement with the rack teeth under theinfluence of a spring -I28. One endof this spring has a connection I29upon the latch and its other end has a connection I30 upon the seatback. This spring is also normally under tension and always urges thelatch into engagement with the rack whe the lever I23 is released.

The flexibility and resiliency of the torsion springs provide forsubstantially unobstructed seat back, or relative to the latter, and theengagement of the lower frame portions of the seat back between thebracket arm extensions 96 that extend rigidly from the seat bottominsure proper following of the lower portion of the seat back inresponse to movements of the seat bottom.

Referring to Figs. '7 to 10 of the drawings, the locking device 53 isoperated somewhat differently from that previously described and thebearing portion 32 ofthe rocker arm 22 extends inwardly 40 to such'position that the bearing brackets 21 and 30 are disposed in' andoperate in substantially the same vertical plane. 'In this arrangementthe bearing portion 32 disposed'in thebearing bracket 30 is at one sideof the rocker arm 22 and the upright angular extension is formedseparately, but the latter is rigidly-secured to an integral a lug I58adjacent its other end for engaging the arcuate rack portion 62 of thelocking sector 60. The lug I58. is normally maintained in engagementwith the arcuate rack by means of a coil spring I59 that is normallyunder compression and. has one end disposed in a socket I60 formed inthe lower side of the dog adjacent its end, and the other end of thespring is disposed in a socket I02 formed in the end of a plug I63 thatis screw threaded through the lower wall forming the cylindrical openingin the handle extension. The plug I53 extends through an opening I05that is formed in the cylindrical portion of the bearing extension I50and that communicates with the recess I51. Thus the end of the plugserves as a key to prevent relative movement of the handle lever 50 andthe bear-. ing extension I50. 76

The handle extension 50 is formed with a longitudinal channel I66communicating through the upper wall forming the cylindrical opening I52and with the recess I51 in the bearing ex- 5 tension. This channelreceives a rod I61 for actuating the dog I55 and its lower rounded endis connected in a socket I68 formed in the outer end of the dog adjacentthe lug I58. The upper end of the rod I61 is pivoted, as indicated atI69, to a short arm I10 of a bell crank I12 that hasits intermediateportion pivoted upon a pin I13 secured in lugs I15 that are formedintegrally upon an intermediate portion of the handle extension. Alonger arm I16 of the bell crank I12 15 extends lengthwise of the uppercurved portion of the handle extension which is in the form of a shelland is cut away to expose the greater portion of the longer bell crankarm I16. A

recess I11 defining the shell portion of the handle 20 communicates withthe longitudinal channel I66 and constitutes a part thereof. By manuallygrasping the upper portion of the handle extension 50 and squeezing itthe longer bell crank arm I16 will be pressed into the recess I11 in theshell-like upper portion of the handle and the shorter arm will bepivoted downwardly to press the rod I61 and dog I55 downwardly againstthe opposed action of the spring I59 to release the lug from the arcuaterack portion '62. Upon releasing the handle 50, together with the armI16, the

spring will again urge the lug I58 into engagement with the rack portion62 of the locking device. Hence, the rocker arms 22 and 23 can beadjusted to various positions between their horizontal and verticalpositions in substantially the same manner as that previously described.In adjusting the seat bottom frame 83 forwardly and rearwardly in theconstruction shown in Fig. '1, a rod I80 is vertically slidable in aguide bracket I82 that is rigidly mounted upon the frame 83. The rod I80extends through the frame into recesses I83 formed in the upper portionof the lifting frame 29 and in a plate I85 rigidly securedto the latter.The lower end of the rod I80 engages in any of these recesses and locksthe frames 83 and 23 against relative movement in various positions ofadjustment. A spring I36 secured between an upper inner shoulder I31 inthe bracket I82 and a shoulder I88 on an intermediate portion of the rodI80 normally urges the rod downwardly into one of the recesses. A handleI89 at the upper end of the rod facilitates its manual operationanddsdisposed at one side of the seat bottom for convenient operation.

From the foregoing description it will be apparent that the seat backcan be adjusted against the resiliency of the torsion springs I02 inupward, downward, rearward directions or tilted from the top or bottom,and that the seat back also co-operates with the seat bottom frame 83 inresponding to all of the adjustments of the latter through the slidingconnection provided by the lugs 86. Likewise, the seat back responds toall adjustments made by manipulating the rocker arms 22 and 23 which arecontrolled by the improved adjusting and locking device 53, the opera-1tionof all of the elements of these constructions being apparent fromthepreceding description.

Inthe form of the invention shown in Figs. 11 and 12,. a lifting andadJusting unit 200 is-- similar in construction to the unit 20 andincludes a front rocker arm 202 and a rear rocker arm 203 on each sideof the seat structure.

' Transverse rods 205 and 206' extending from one'side of the unit tothe other are integrally be stiffer or stronger than the other.-

connected to the front and rear rocker arms 202 and 203, respectively,and are rotatably mounted in bearing brackets 201 carried rigidly uponthe supporting bars I5. The rocker arms 202 and 203 extend rigidly andsubstantially at right angles to the transverse rods 205' and 206, andare pivotally movable in parallel relation from substantially horizontalto substantially vertical positions. v,

The lifting unit200 further includes asubstantially horizontal frame 208havingbearing brackets 208 in which offset front and rear hearingsections 2I0 and 2, provided by bending portions of the'rocker arms, arejournalled. In their parallel movement the rocker arms 202 and 203 carrythe frame 208 substantially horizontally in all of their positions.

Instead of employing a plurality of arms or projections similar to thearms 31 and", the

intermediate portion of the transverse bearing rod 206 is provided witha bent U-shaped portion 2I5 projecting from the axial line containingthe bearing portions of the rod 206 and at an angle to the rocker arms203. A pair of coil springs 2I6 and 2", normally under tension havetheir rear end portions connected, as indicated at 2I8, to the bentportion of the transverse bearing rod and their front end portionsconnected, as indicated at 2I9, to the intermediate portion of the fronttransverse bearing rod 205. I

In one form of the invention either of the coil springs 2I6 or 2" is ofa lesser normal length inuntensioned condition than the other spring;but is composed 'of material having the same characteristics, includingthickness, diameter and coeflicient of resilience. Thus, when .therocker arms are in the region of a vertical position the longer of thetwo springs is in a relatively relaxed condition and exerts aproportionately lesser pull upon the bearing rod 206. When the liftingunit is in:a downward and rearward position and the rocker arms are inthe region of a horizontal position, the longer of the two springs iselongated and is under greater tension, and thereby assists the otherspring to a greater extent in urging the rocker arms upwardly.

This arrangement provides an increased spring force urging the U-shapedportion 2I5 upwardly and forwardly when the rocker arms are in theregion of a horizontal position which is necessary in order that thelifting unit shall work smoothly and evenly and without any extraexertion or effort on the part of the user. 4

In another form of the invention either one of the springs 2I6 or 2" maybe made of material having characteristics different from those in theother spring, so that one of the springs will Springs so constructedhave so-called deflections of different values, and deflection", withreference to springs,

is intended to convey the meaning of travel, in inches, of the springunder application of specifled load in pounds. Thus, either a relativelystiffer spring or a relatively weaker spring having a greater normallength than the other maybe provided in order that the device may haveany desired capacity; and although the particular arrangements ofsprings shown in the drawings serve their purpose, itis to be understoodthat various combinations of springs of different strengths and normallengths are employed according to the weight to be lifted and the sizeand arrangement of the structural elements with which they areincorporated.

- The'prizflpal improved results to be secured involve the provision ofsprings so designed that their maximum force is applied when the rockerarms are in their substantially horizontal position, and the minimumspring force is applied when the rocker arms are in their substantiallyupright position. The springs are selected to cooperate efliciently inconjunction with the supporting of persons having a relatively widerange of weights atthe many various levels to which the seat isadjustable so that the device may be readily adjustable upon theapplication of a uniform and minimum amount of exertion or effort on thepart of the operator.

The rocker arms 2'02 and 203 at one side of the unit 200 are providedwith upwardly projecting angular extensions 220 and 222 respectively,which are parallel to each other and are integral with the bearingportions 2| 0 and 2, respectively. These extensions provide pivotalsupports 225 and 226, for a locking device 221, and

these pivotal supports are spaced equally from the axes of the rockerbearing portions 210 and 2| I, respectively. The locking device includesa bar portion 228 which serves as a brace to cooperate with the frame208 in maintaining proper parallel relation of the rocker arms and com-'pensating for whatever looseness that may occur in the bearing brackets201 and 209 supporting these rocker arms. The parallel relation of theseso elements is the same as that previously described with reference tosimilar elements connecting the locking device 53.

The forward end of the locking device 221 is formed with a rigid sector229 that has an arcuate w rack portion 230, the line of curvature ofwhich is drawn about an axis, for example, the axis of the pivotalsupport 225, ofiset upwardly from the axis of the pivotal connection 2 I0. The arouate rack portion 230 faces downwardly and in the m rockingmotion of the rocker arms the edge of this rack portion passestransversely across the upper extension 220 of the front rocker arm.

A locking lever 232 of bell crank form includes rigid arms 235 and 236disposed at acute angles to 45 each other and the lever has a pivotalconnection 231 at the junction of the arms securing it to the outer sideof an upturned flange 230 of a plate 230 rigidly mounted upon an edgeportion of the seat frame 208. The flange 238 is spaced from the 50 edgeof the seat frame 208. The free end of the lever arm 235 is providedwith an outwardly turned integral finger 240 which is adapted to engage.various portions of the sector rack 230 according to the position ofthe rocker arms 202 and 55 203. The other lever arm 236 is provided witha finger piece 243 which is manually operable to disengage the finger240 from the sector rack. The pivotal movement of the lever is limitedby a stop 245 which is'mounted upon the plate 239 be- 60 tween the twoconverging arms 235 and 236 and one end ofthe rack 230 is provided witha relatively long projection 246 which lies in the path of the finger240 regardless of whether the finger is in its lower or disengagingposition, or in 65 (its engaging position with respect to the rack.

One end of a coil spring 241 has a connection 248 for securing it to thearm 236 of the lever, and the other end of the spring has a connection240 for securing it to a bracket 25! on the seat frame 208. This springis normally under tension and constantly urgesthe finger 240, toward itsposition of engagement with the rack 230, and prevents accidentaldisengagement therefrom. A second bell crank lever 250 which is mounted75 by means of a pivotal connection 252 upon the inner side of the plateflange 238, is provided with converging arms 255 and 256 disposed at anacute angle to each other. The lower arm 255 is formed with a finger 251at the outer end thereof for engag'ement with a rack 258 secured to thelower side of the seat frame 83. Since the construction of the seatframe 83 in Fig. 12 is the same as that previously described its partsare designated by j the same reference characters as those previouslyemployed. A finger piece 259 at the end of the other arm is adapted tobe manually operated to release the seat frame 03 from its lockedrelation with the lever in order that it can be moved forwardly orrearwardly upon the rocker arms 90. One end of a coil spring 260 has aconnection 262 for securing it to the arm 256 of the lever 250 and theother end of the spring has a connection 263 for securing it to thebracket 25| on the seat frame 208. This spring is normally under tensionand constantly urges the finger 251 toward. its position of engagementwith the'rack 258 and prevents accidental disengagement therefrom.

In operating the construction shown in Figs. 11 and 12, the operator canmanipulate either of the finger pieces 243 or 259 and shift his weightforwardly or rearwardly depending upon the relative position of theparts. By employing the steering wheel of an automobile as a means forassisting in shifting his weight, an operator can, with very slighteffort, adjust the position of the rocker arms 202 and 203 and, hence,the position of the seat structure with reference to its height, orforward and rearward position. In like manner, the frame 03 aspreviously described, can be adjusted forwardly and rearwardly upon theunit 200.

Although several forms of the invention have been shown and described indetail, it will be apparent to those skilled in the art that theinvention is not so limited, but that various changes can be madetherein without departing from the spirit of the invention or from thescope of the appended claims.

What is claimed is:

1. In a seat structure, front and rear rocker arms movable betweensubstantially horizontal and vertical positions, means for pivotallysupporting the rocker arms, a seat frame mounted upon the rocker armsand movable with the rocker arms to various adjusted positions, alocking device having pivotal connections supporting it upon the rockerarms for movement therewith, locking means carried by one-of the armsand normally engaging the locking device to lock the rocker arms invarious positions between their horizontal and vertical limits ofmovement, and means carried by one of the .rocker arms for actuating thelocking means.

2. In a seat structure, front and rear seat supporting rocker arms,means for pivotally supporting the rocker arms, a member pivotallyjoining the rocker arms at locations spaced from the pivotal supportingmeans, said member having a locking sector, rigid therewith adjacent oneof the pivotal connections of the member upon one rocker arm, alockingmember carried by thelatter rocker arm and releasably engagingthelocking sector, actuating means carried by said latter rocker arm forreleasably engaging and disengaging the locking member whereby therocker arms can be locked in various positions about their pivotalsupports.

3. In a seat structure, front and rear rocker arms movable betweensubstantially horizontal and vertical positions, means for pivotallysupmounted upon the front rocker porting the rocker arms, upon therocker arms and movable with the latter to various positions ofadjustment, a locking device having pivotal connections supporting it 5upon the front and rear rocker arms for movement therewith, said lockingdevice having. an arcuate indented edge disposed about thepivotalconnection of the locking device upon the front rocker arm, amovable locking member arm and normally engaging the indented edge forlocking the rocker arms and frame against relative movement, and meanscarried by the front rocker arm for actuating the locking member.

4. In a seat structure, front and rear rocker arms movable betweensubstantially horizontal and vertical positions, means for pivotally,supporting the rocker arms, a seat frame mounted upon the rocker armsand movable with the latter to various positions of adjustment, alooking bar having a sector plate formed at one end thereof, means forpivoting the sector plate to the front rocker arm, means for pivotingthe end of the bar opposite the sector plate 'to the 2 other rocker arm,the sector ,plate having an edge of rack-like form, a locking membercarried by the front rocker arm and normally engaging the rack-likesector plate to lock the rocker arms and frame against relativemovement, and means a seat frame mounted carried by the front rocker armfor actuating the locking member.

5. In an adjustable seat structure, a seat frame, front and rear rockerarms having projections angularly movable and having upper portionsconnected to the seat frame for moving the latter upwardly and.forwardly to various positions ofadjustmerit,

otally connecting the front and rear rocker arms,

able with respect to seat frame in the rocking motion of the rockerarms, means carried by the seat frame for engaging the rack portion inlocking relation in various positions of the rock- 45 er arms, and meansfor actuating the rocker 6. In an adjustable seat structure, a seatframe, front and rear rocker arms having projections angularly movableand connected to the 50 seat frame for moving the latter upwardly andforwardly to various positions of adjustment, means for supporting therocker arms, a locking member pivotally connecting rocker arms, saidlocking member having a rack 5 portion movable with respect to the seatframe in the rocking motion of the rocker arms, a lever pivoted to thegag'eable with the rack portion forlocking the rocker armsinvariouspositions of adjustment.

'1. In an adjustable seat. structure, a seat frame, front and rearrocker arms having rigid projections angularly movable and connected tothe seat frame for moving the latter upwardly 65 and forwardly tovariouspositions of adjustment, means for supporting the rocker arms, alocking device including rear rocker arm projections and movable inparallelism'with the seat frame, said bar having a 6 locking rackformedtherewith, a lever pivoted to the seat frame and having meansengageablewith the locking rack for locking the rocker arm projections ln'variouspositions of adjustment. 7 8. In a seat structure, front and rear rocker75 arms movable between substantially horizontal means for pivotallysup-- porting the rocker arms, a locking member piv-,

the front and rear seat frame and having means en ing radially a barconnecting the front and and vertical positions, means for pivotallysupporting the rocker arms, a seat frame having pivotal connectionssecuring it to the rocker arms for movement with the latter tovariousadjusted positions, a locking device having pivotal connectionssupporting it upon the rocker arms for movement therewith, locking meanscarried by one of the arms and normally engaging the locking device tolock the rocker arms in various positions between their horizontal andvertical limits of movement, and means carried upon one of the rockerarms for actuating the locking means, the latter rocker arm projectingin the form of a lever handle to support the last mentioned means and tofacilitate manual operation of the rocker arms.

9. In a seat structure, an'adjustable unit including a seat frame, saidunit also including front and rear arms pivotally supporting the frame,supporting means pivotally supporting said arms at locations spaced fromthe pivotal connections thereof to the frame, a locking member pivotallyconnected to front and rear arms of the unit, said member having lockingmeans formed thereon substantially radially disposed about one of thepivotal connections of the locking member, means connected to the unitfor releasably engaging the locking means for locking the arms invarious positions of adjustment, and means for maintaining the pivotalaxes of the pivotal connections of said arms substantially parallel andhorizontal. 1

10. In a seat structure, an adjustable unit including a seat frame, saidunit also including arms pivotally supporting the frame, supportingmeans pivotally supporting said arms at locations spaced from thepivotal connections thereof to the frame, means for maintaining thepivotal axes of the several pivotal connections of said armssubstantially parallel, and horizontal, a lockin device connected tosaid unit for selectively looking the latter in various positions ofadjustment upon said arms, a plurality of projections rigid with respectto one of the arms and extending .at diflerent angles to the latter arm,a plurality of resilient members connected to the projections atlocations spaced different distances from the pivotal axis of saidlatter rocker arm, and means for anchoring the resilient members to saidsupporting means atlocations remote from said latter arm.

11. In a seat structure, a movable unit includ- I ing front and rearrocker arms, said unit also including a seat frame pivotally carried bysaid arms, a rod rigidly joining the front rocker arms,

a second rod rigidly joining the rear rocker arms,

supporting means pivotally anchoring the rods of the front and rear armswhereby the unit is pivotally movable through predetermined angles uponthe supporting means, a locking device connected to said unit forselectively locking the latter in various positions of adjustment uponsaid arms, a plurality of projections rigidly mounted upon the rod ofthe rear rocker arms and extendv at angles to one another and at anglesto the direction of extension of the latter rocker arms, a plurality ofresilient members connected to the projections at locations spaced fromthe axis of the rear rod, and means for connecting the resilient membersto the integral rod of the front rocker arms.

12'. In an adjustable seat structure, a movable unit including angularlymovable front and rear rocker arms, said unit also including a framepivotally carried by the arms in varlouspositions,

supporting means pivotally supporting the rocker arms at locationsspaced from the pivotal connections thereof to the frame, means foradjusting the rocker arms in various degrees between substantiallyhorizontal and substantially upright positions in their angularmovement, a spring normally under tension connected to said unit at alocation spaced from said supporting means and exerting force tending topivot the arms toward 10 an upright position, means for connecting saidspring to said supporting means, a second spring normally under tensionconnected to said unit at a location spaced from said supporting meansand exerting force also tending to pivot the arms toward an uprightposition, the deflection of the second, spring being greater than thedeflection of the first spring.

13. In an adjustable seat structure, a movable unit including angularlymovable rockerarn'is, said unit also including'a frame pivotally carriedby the arms in various positions, supporting means pivotally supportingthe rocker arms at locations spaced from the pivotal connections thereofto the frame, means for adjusting the rocker arms in various degreesbetween substantially horizontal and substantially upright positions intheir angular movement, a first spring normally under tension connectedto one rocker arm at a location spaced from the pivotal supporting meansof the arm and exerting force tending to pivot the arms toward anupright position, means for connecting said spring to said supportingmeans at a location spaced from said one rocker arm, a second springnormally under tension connected to saidone rocker arm at a location agreater distance from the pivotal supporting means than the connectionof the first spring to said arm and exerting force tending to pivot saidone arm toward an upright position, means for connecting said secondspring to the supporting means at a location spaced from said one rockerarm, the deflection of the first spring being greater than thedeflection of the second spring.

14. In a seat structure, a movable unit including front and rear arms,supporting means pivotally supporting said arms about horizontal axes,said unit also including a member having pivotal connections with frontand rear arms at locations spaced from said means, a bar pivotallyconnecting front and rear arms of the unit at locations radially spacedfrom said supporting means and from said connections, an arcuate rackcarried rigidly by said bar and having its circumferential rack portiondescribed about the pivotal axis of one of the pivotalconnections ofsaid bar as a center, rack engaging means selectively engageable withthe arcuate rack section for locking the arms in various positions, andmeans for sup- 00 porting said rack engaging means on said unit.

15. In a seat structure, a movable unit including front and rear arms,supporting means pivotally supporting said arms about horizontal axes,said unit. also including a member having pivotal connections with saidarms at locations spaced I from said supporting means, a bar pivotallyconnecting front and rear arms of the unit at locations radially spacedfrom said supporting means and from said connections, said bar having arack section formed thereon, raclmengaging means sef lectivelyengageable with the rack section for.

locking the arms in various positions, and means for supporting saidrack engaging means on said unit.

16. In a seat structure, a movableseat suppivotal supports. l0

17. In a seat structure, a movable seat supporting and adjusting unitincluding front and rear arms, means for carrying a seat on said unit,supporting means pivotally supporting said arms about horizontal axes, abar pivotally connecting l5 front and rear arms of the unit at locationsspaced from said supporting means, an arcuate rack section formed on thebar and having its circumferential rack forming portion described aboutthe pivotal axis of one of the 20 pivotal connections of said bar as acenter, and

rack engaging means supported by at least one of said arms andselectively engageable with the arculate rack section for locking thearms in various positions.

18. In an adjustable automobile seat structure for positioningautomobile operators at various elevations in an automobile body, a seatsupporting unit including a seat frame, said unit also including frontand rear arms having upper pivotal connections securing them to theframe and said arms being movable from a substantially horizontalposition to an upright position, supporting means having lower pivotalconnections securing and supporting said arms at loca- 86 tions spacedfrom the upper pivotal connections thereof to the frame whereby the armscarry the seat unit between a lower rearward position and an upperforward position, means for maintaining the pivotal axes of the severalpiv- 40 otal connections of said arms substantially parallel andhorizontal, a projection rigid with respect to one of the arms andextending in a substantially upright position in the lower rearwardposition of said unit and being movable down- 45 wardly about the lowerpivotal connection of v the latter arm in response to movement of theunit toward'an upper forward position, a resilient member urging saidarms pivotally from a lower position upwardly about said supporting 59means, said resilient member having an end connected to the outer endportion of said projection, and means for anchoring the other end of theresilient member with respect to said supporting means at a locationremote from said 55 latter arm.

19. In an adjustable automobile seat structure for positioningautomobile operators at various elevations in an automobile body, a seatsupporting unit including a seat frame, said unit also 60 includingfront and rear arms having upper pivotal connections securing them tothe frame and saidarms being movable from a substantially horizontalposition to an upright position, supporting means having lower pivotalconnec- 55 tions securing and supporting said arms at locations spacedfrom the pivotal connections thereof to the frame whereby said armscarry the seat unit between a lower rearward position and an upperforward position, means for maintain- 70 mg the pivotal axes of theseveral pivotal connections of said arms substantially parallel andhorizontal, a projection rigid with respect to one of the rear arms andhaving an upwardly projecting outer end portion located forwardly 15 inthe space beneath said unit and having one end connected to the outerend portion of said projection, and .means for anchoring the other endof the resilient member to a member stationary with respect tosaid,supporting means at a location remote from said latter arm andforwardly of the latter.

20. In an adjustable automobile seat structure for positioningautomobile operators at various elevations in an automobile body, a seatsupporting unit including a seat frame,- said unit also including frontand rear arms having upper pivotal connections securing them to theframe and said arms being movable from a substantially horizontalposition to an upright position, supporting means having lower pivotalconnections securing and supporting said arms at locations spaced fromthe pivotal connections thereof to the frame whereby the arms carry theseat unit between a lower rearward position and an upper forwardposition, means for maintaining the pivotal axes of the several pivotalconnections of said arms substantially parallel and horizontal,

a locking device connected to said unit for selectively locking thelatter in various positions of adjustment upon said arms, a projectionrigidwith respect to one of the rear arms and'ex- BAYMON E. ROUSSEAU. 2

